Screw-propeller.



Nd. assaut. Patemd Feb. 2s, mol.

n. wl-:sTPHAL-EN. I

SCREW PRDPELLER.

(Application led Nov. 21, 1599.)

(No Ilodei.)

. streit.

RUDOLF WESTPHALEN, OF VIENNA, AUSTRIA-HUNGARY;

SCREW-PROPELLER.

SPECIFICATION forming part of Letters Patent No. 668,701, dated February 26, 190i, Application inea November 21, i899. serai No. '737.746. cio model.)

To all whom, t may concern:

Beit known that I, RUDOLF WESTPHALEN, a subject of the Emperor of Austria-Hungary, residing at Vienna, in the Province of Lower Austria and Empire of Austria Hungary, have invented new and useful Improvements in Screw-Propellers, of which the following is a specification.

This invention relates to propellers for vessels acting on the principle of the screw-that is to say, in which a number of inclined blades are secured to a revolving shaft which is arranged parallel to the keel of the vessel, the said blades projecting a mass of water in a direction opposite to that of the required motion of the vessel. As the speed of a vessel thus propelled is a function of the reaction of the mass of water projected backward and as the amount of reaction directly depends on the mass of the moving water and on its velocity, the invention has for its object to increase the mass of water simultaneously in motion by doing away with one of the causes by which with ordinary screw-propellers the m's ui/ua of the moving particles of Water is prematurely absorbed. This cause is the current of water drawn after it by the boss of screw-propellers of the usual construction, the said current being in frictional contact with the streamlines of the current projected sternward by the propeller-blades.

According to the invention the propeller is so constructed that the boss,by means of which it can be connected to the driving-shaft, is not arranged between the blades, but in front of them. Two or more suitably-inclined plane blades, by preference of circular shape, are so arranged side by side as to touch each other with one point of their circumferences, and from a suitably-chosen point of the rear faces of the said blades converging bars extend to the boss for connecting the blades with the boss.

In order that the connecting-bars, instead of creating by their rotation Within the water a detrimental resistance, concurin producing the sternwardly-directed current of water, the said bars are flattened and arranged with such inclinations toward the axis of the boss as to act as propeller-blades.

In order to make the invention fully understood, the same is hereinafter described with reference to the accompanying drawings, in which- Figure l is a side elevation of a two-blade propeller of the construction referred to above; Fig. 2, a rear elevation, and Fig. 3 a top view, of the same.

It will be seen that the two circular blades a a have plane rear faces, while the front faces are somewhat vaulted in order to give all port-ions the requisite strength. It is 0bvious that quite as well the front faces may be made plane and the rear faces vaulted. The blades a a touch each other at a point b of their circumferences and are in opposite directions inclined toward the axis of the boss d. In the case of three or more blades the same would have the positions of symmetric tangential planes to supposed equidistant helical blades.

From the centers of the blades d a the converging bars c c extend to the boss d. These bars c c are liattened, and, as may be inferred from their lines of intersection with the surface of the boss, they are so inclined toward the axis of the boss that when turning they set the water in motion in a similar manner as the blades a a. The positions of these flattened bars c may be defined as those of symmetric tangential planes to as many equidistant helical surfaces generated by generatrices which are inclined toward the axis of the supposed cylindric core. For the purpose of reducing the resistance against the movement of the bars c in the lateral direction the said bars have their front faces vaulted, whereby sharp edges are obtained.

What I claim, and desire to secure by Letters Patent of the United States, is-

l. In a screw-propeller, the combination with a plurality of plane blades, having the positions of sym metric tangential planes to as many equidistant helical blades, and being so arranged side by side as to touch each other at one point, of a boss located in front of the said point, and converging bars, which connect a point of the front face of each blade with the boss, substantially as and for the purpose described.

2. In a screw-propeller, the combination with a plurality of circular plane blades, having the positions of symmetric tangential planes to as many equidistant helical blades,

IOO

and being so arranged side by side as to touch each other at one point of their circumferences, of a boss located in front of the said point, and converging bars, which connect the centers of the front faces of the said blades with the boss, substantially as and for the purpose Set forth.

3. In a screw-propeller, the combination with a plurality of plane blades, having the positions of symmetric tangential planes to as many equidistant helical blades, and being so arranged side by side as to touch each other at one point, of a boss located in front of the RUDOLF WES'IPIIALEN.

Witnesses:

VIXSAR VRENZEL, ALvEsTo S. HoGUE. 

